On 13 February 2026, a yacht sank off Gran Canaria after a collision with an unknown object. All five people on board were rescued unharmed. The accident is one of a loose chain of serious damage or ship losses, the cause of which can never be fully clarified. How can sailors protect themselves from UFOs - Unidentified Floating Objects? An overview of an underestimated danger and modern solutions.
Once again, the news makes people sit up and take notice: A sailing yacht collides with a large, unknown object and suffers such severe damage that it sinks within minutes. This is what happened on 13 February 2026 off Gran Canaria. The owner of the Bavaria 45 and his crew are not the only ones who subsequently wonder what could have caused such a large leak that the yacht sank within minutes. In October 2023, the "Jambo" of single-handed sailor Martin Daldrup sank in the South Atlantic in a similar way. Daldrup also assumes the Collision with a large, unknown object from. In the Golden Globe Race 2022 the Finn Tapio Lehtinen lost his Gaia 36 "Asteria" 460 nautical miles south-east of Cape Town for unknown reasons and had to be rescued by his racing rival Kirsten Neuschäfer.
These are the better-known cases; most receive less attention. But probably every sailor knows such stories of unpleasant collisions or - with luck or thanks to an attentive lookout - obstacles noticed at the last moment on or just below the surface of the water. The worry travels with you, sometimes more, sometimes less present.
No AIS and incomplete warning systems
Lost containers, driftwood, fishing gear and other floating objects have no AIS. They are practically invisible to sailors. Radar only detects objects above water. Anything floating half or fully submerged remains undetected - until a collision occurs.
Some objects are equipped with AIS or GPS tracking: Weather buoys from national weather services, oceanographic research buoys, some fishing equipment and autonomous underwater vehicles on active missions transmit position data. However, the far greater danger comes from objects without any identification.
These include, in particular, containers, thousands of which go overboard worldwide every year. Some sink immediately, others float just below the surface for weeks. Depending on the cargo, they can float half-submerged for weeks - a nightmare for any sailor.
Warning systems such as NAVWARN and NAVAREA warnings via NAVTEX and weather radio do exist, port authorities and shipping companies also report container losses, and the International Maritime Organisation (IMO) runs the Global Integrated Shipping Information System (GISIS). But the reality is sobering: there is no obligation to report lost containers immediately and publicly. The information is often delayed. A central database accessible to sailors is missing, as is a tracking system for drifting objects.
Also travelling unrecognised are thousands of FADs (Fish Aggregating Devices), small oceanographic drifters, abandoned fishing nets - so-called ghost nets - and wreckage.
Whale carcasses floating just below the surface are particularly dangerous. There is also driftwood and tree trunks, especially after storms, but also pontoons, unlabelled buoys and even military objects such as submarine drones or training targets.
How likely is a collision?
The sober statistics sound reassuring at first: according to the latest report by the World Shipping Council, which was published in June 2025an estimated 576 containers were lost in 2024 - with around 250 million containers transported, this corresponds to a loss rate of just 0.0002 per cent. The increase compared to 2023 with 221 lost containers is mainly due to the rerouting of ships around the Cape of Good Hope due to the tensions in the Red Sea, where 200 containers alone went overboard.
In the long term, the trend shows a clear improvement: the ten-year average is 1,274 containers per year. However, individual accidents can drastically increase the statistics - in 2020, a freighter in the Pacific lost 1,900 containers at once, while the MSC Zoe lost 342 of its 8,062 containers in the southern North Sea in 2019. Since 1 January 2026, it has been mandatory to report all container losses to the IMO, which should improve the data situation.
However, it is almost impossible to quantify the actual danger to sailors. This is because many collisions with so-called UFOs - Unidentified Floating Objects - remain unexplained. In most cases, the steel structures weighing several tonnes quickly sink to the seabed. It is "extremely rare" for containers to drift just above or below the surface of the water, says Holger Flindt from insurance broker Pantaenius. Collisions with other flotsam such as nets, tree trunks, rafts or Euro pallets are more likely - as are collisions with marine mammals.
Where is the danger greatest?
The main shipping routes harbour the highest container risk. The Strait of Gibraltar, the English Channel and the North Sea are high-risk areas, as are the routes between the Canary Islands and Pacific routes after storms. The risk increases wherever there is intensive container traffic between Asia, Europe and America.
The risk increases after extreme weather events. Hurricanes, hurricanes and typhoons leave behind massive fields of debris, tsunamis wash everything that wasn't nailed down into the sea. Severe winter storms in the North Atlantic and the monsoon season in Asia regularly pose new dangers.
Waters close to the coast are particularly critical in estuaries. Tree trunks and civilisation waste from the Rhône, Po, Rhine or Ebro drift into the open sea. After land storms, washed away material becomes a serious threat.
Other dangers lurk in fishing areas: In the North Atlantic it is lost longlines and nets, in the Mediterranean illegal nets, in the Pacific the FADs of the tuna fleets and off the coasts of West Africa a combination of everything.
Particular risk zones are the Bermuda region with a lot of traffic and the Gulf Stream, which drives objects, the Bay of Biscay with strong storms and high traffic, the Bass Strait in Australia with extreme conditions and the notorious Drake Strait, where everything that floats there is dangerous.
Can the lookout recognise UFOs in time?
The sobering answer is: it depends - and even experienced sailors regularly overlook drifting objects. A fully loaded container sometimes protrudes 20 to 30 centimetres out of the water and is easily recognisable in calm seas. In rough seas, however, it disappears between the waves. What was visible as a dark spot on one wave is invisible on the next.
Half-flooded containers are even more treacherous. They float just below the surface, often only 20 to 50 centimetres deep. In daylight, you can sometimes make out a dark shadow in the water - if you look closely and the sun is favourable. With backlighting, waves or cloudy skies: no chance. Empty containers often tip on their side or float on edge, which makes them clearly visible in calm seas - but they also disappear in the trough of the waves.
The lighting conditions play a decisive role. When the sun is low, objects on the water are practically invisible due to backlighting, the reflection outshines everything. At night, even a large container is completely invisible without moonlight. Only if it is brightly painted and reflects moonlight is there a minimal chance. Twilight is the most critical time: the eye adapts to changing light conditions and contours become blurred. Cloud cover massively reduces contrasts due to diffuse light.
Driftwood and large tree trunks usually float horizontally and barely protrude from the water. Their brownish colour blends in with the sea. They are practically invisible in rough seas. The different texture of the surface can only be recognised from a few metres away - often too late at a speed of 7 knots. Trunks with roots that protrude underwater like tentacles and can get caught in the rudder or keel are particularly dangerous.
Some fishing buoys are easily recognisable thanks to radar reflectors or paint. Much more frequently, however, fishermen use simple constructions made of wood, plastic canisters or nets - often in shades of brown, grey or green and marked with tiny buoys. In calm seas, they are barely recognisable; in rough seas, they disappear completely. Drifting nets are the most invisible danger of all. They float just below the surface, often with accumulated fouling that colours them dark. Sometimes they can be recognised by a slight discolouration of the water or the formation of foam, but usually nothing. Although they do not have what it takes to cause massive damage to the hull of a yacht, they can become a serious danger if they get caught on the steering gear or in the propeller.
A dead whale usually lies almost completely under water, with only its back bulging slightly. When the sea is calm, it looks like a dark wave or a smooth rock. In rough seas, it is invisible. The danger: carcasses are massive and immobile.
So what should the lookout look out for? Changes in the wave pattern can indicate objects that interfere with the waves. Dark spots or shadows are particularly visible in sunlight. Foaming occurs because waves break differently on objects. Discolouration in the water indicates flotsam, on which algae often accumulate. Seabirds like to perch on floating objects. And unusual reflections from metal or plastic differ from the natural play of waves on closer inspection.
But even the most attentive lookout reaches its limits. A person cannot monitor 180 degrees at the same time. After 20 minutes, attention wanes considerably. At night, during long waking hours, perception drops drastically. And reaction time is crucial: it takes 2 to 3 seconds from recognition to reaction - at 7 knots, that's almost 20 metres covered.
But the reality at sea with changing light, swell, fatigue and night hours makes it almost impossible to detect all dangers in time.
Constructive protection: collision bulkheads and material issues
Ideally, structural measures can prevent or at least delay sinking. For example, collision bulkheads - watertight partitions in the bow and sometimes also the stern area - are quite common on ocean-going yachts, but are not standard. They divide the boat into separate watertight compartments. If the bow is damaged by a collision, the rest of the hull theoretically remains dry. But the reality is more complex: a collision bulkhead only provides protection if the damage is limited to compartmentalised areas. Very few boats are equipped to absorb massive damage that may occur amidships or over a larger area.
There is also no clear answer to the question of materials. Boats made of steel or aluminium are considered robust, but they can also dent or tear in collisions with hard objects such as containers. GRP boats can break open or get holes if hit hard. Finally, wooden boats can splinter.
The decisive factor is not so much the material as the construction and reinforcement. Modern offshore yachts often have reinforced bow areas, thicker laminate layers in critical areas and more robust collision bulkheads. Regatta IMOCAs are lightweight and therefore more vulnerable, while cruising yachts are usually more solid. However, in a collision with a container weighing several tonnes at a speed of 7 to 9 knots, these differences often only play a minor role. The kinetic energy is enormous, and no leisure boat is designed to survive such collisions without damage. The most important protection remains: Not allowing the collision to happen in the first place - through vigilance, technology and anticipatory navigation.
Equipment: The intelligent lookout assistant
In the meantime, Sea.AI is a Technical support for the lookout. The successor to the system previously known as "Oscar" uses camera technology in combination with artificial intelligence to recognise objects that conventional systems such as radar or AIS miss: unmarked boats, floating obstacles, buoys, inflatable boats, kayaks and people overboard. The sensors and software are related to the technology used for autonomous driving in the automotive sector.
The masthead-mounted system combines thermal imaging and daylight cameras and analyses the image data in real time on board - independently of an internet connection. There are three main variants: Sea.AI "Competition" for regatta sailors (from 23,890 euros), "Sentry" for commercial shipping and "Offshore" for cruising sailors. The cheapest offshore version, "Offshore One", costs 10,990 euros. It detects cargo ships on the horizon, yachts from 1,000 metres away, small boats from 250 metres and people, buoys and smaller flotsam from 100 metres in front of the bow. The device weighs 900 grams and is connected to the on-board network via NMEA 2000.
For owners who already have a thermal camera installed in their rig, Sea.AI with the Brain, a retrofit solution for 7,990 euros. The box is connected to the existing camera, analyses the camera image, recognises objects in real time, marks them and issues warnings. The crew can set individual threshold values for alarms, such as the distance or object size at which a warning should be issued.
The French shipyard Privilège Marine is the first multihull shipyard in the world to make Sea.AI standard equipment for its entire model range, while the Danish shipyard X-Yachts offers it as an option.
However, Sea.AI is not yet an alternative to radar or AIS, but a supplement. It cannot detect land, rocks or weather fronts. The integration of the system with traditional navigation media is still under development.
What sailors can also do
For many sailors, technical equipment with intelligent camera systems will be a question of budget. Even without them, the risk can be minimised through forward planning and increased vigilance. NAVTEX and NAVAREA warnings should be checked before the voyage, and contact with local harbour authorities can also provide important information on current dangers.
Sailing communities and regional forums are valuable sources of information, as are social media channels, through which warnings are sometimes disseminated more quickly than through official channels. Asking boats ahead can provide specific information about floating debris in certain areas. The following applies during the voyage: night watches must be kept with particular vigilance and radar should be used actively, even if it only shows objects above water. Particular caution is required at night on main shipping routes, and vigilance should generally be increased after storms.
Adjusting speed in poor visibility sounds obvious, but is often neglected. In heavy traffic or in known risk areas, sailors should consider investing in systems such as Sea.AI. After an incident with UFOs, it is important to report sightings to the coastguard and share information in sailing communities - with position and exact description. This is the only way to warn other sailors.
Ursula Meer
Redakteurin Panorama und Reise
